1.Everyone shall possess the right to freely express and publicise his thoughts in words, images or by any other means, as well as the right to inform others, inform himself and be informed without hindrance or discrimination
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Constitution of the Portuguese Republic, Article 37.º

The private investigator hired by Kate and Gerry McCann to find their daughter said today he knows who took Madeleine and is close to reuniting her with her parents.

Francisco Marco said the missing four-year-old has been kidnapped by a paedophile ring and is being held in north Africa or the Iberian Peninsula.

In his boldest claim yet, the director general of Metodo 3 also said he hoped the McCanns will have their daughter back by Christmas.

He said: "We know who kidnapped her. We believe she is in an area not very far from the Iberian peninsula and north Africa. And we have a fairly certain idea of who she is with.

"I cannot say who she is with because we are putting together conclusive proof we can present to the authorities so they can proceed with their arrests."

Insisting he believed Madeleine was still alive, Mr Marco added: "God willing, I hope she'll be back with her parents before Christmas."

The Barcelona-based Metodo 3 has been working for the McCanns since September and Mr Marco has already travelled to Morocco to follow up a reported sighting of a blonde girl with the same distinctive marking as Madeleine in her right eye.

However it is not the first time the agency has made extremely optimistic, occasionally reckless, claims about the case's progress.

Last month Francisco Marco again told a BBC Panorama team that the agency was "100 per cent sure Maddie is alive."

He added: "We're sure she was abducted and we are very, very close to finding those responsible."

The claim caused an embarrassed Clarence Mitchell, the McCann's official spokesman, to brief the media that the private detective had simply got "carried away".

The agency claims to have around 35 investigators working on the case and is being paid £50,000 a month by the Find Madeleine Fund.

Mr Marco also promised last month that he would find Madeleine, who disappeared on 3 May from a holiday apartment in Praia da Luz in the Algarve in Portugal, before Metodo 3's six-month contract runs out next March.

Mr Marco said: "I have always said publicly Madeleine is alive. I have to believe it 100 per cent because I know how to look for living people, not dead ones. But I have no proof Madeleine is alive.

"We have proof of her movements after her kidnap and we know she was alive the day after her disappearance. We are not certain she left Portugal.

"I talk of certainties because we know which group may have her or could have kidnapped her to then sell her on to others."

He continued: "One of the things that makes us believe Madeleine is alive is

that every day she's worth more to them. It's obviously not a kidnap carried out by professionals for economic reasons.

"A professional kidnapper would have done something with Madeleine by now. He would have given her back or left her."

Metodo 3 has been criticised by Portuguese police as "small fry" and "irrelevant".

Relatives of Robert Murat, who remains an official suspect in the case, have accused the agency of trying to frame him by pressuring witnesses into changing their statements.

In the interview with the Spanish newspaper-Metro, Mr Marco added: "It's the highest pressure case I've ever had to deal with, because of the press and because of my own family.

"When I get home at night, my children ask me, 'Have you found Madeleine yet, daddy?'"

Dismissing the suggestion of any involvement by the McCanns, who were declared official suspects in their daughter's disappearance after she vanished from the Ocean Club apartment complex, he said:

"You only have to spend five minutes with them to realise they've got nothing to do with this.

"To this day there's no proof of any traces of blood in the flat. In the boot of Gerry and Kate's hire car, so people say, there's traces of a tiny hair that could be Madeleine's.

"But that would be completely logical and normal being the family's car."

Repeating his earlier promise to find Madeleine before March, he said: "We have a six-month contract. We have always said we want to fulfill it by finding her."

Clarence Mitchell, spokesman for the McCanns, said the family has "absolute confidence in Metodo 3".